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Sharpless oxidation 1.3 -shift

The asymmetric oxidation of sulphides to chiral sulphoxides with t-butyl hydroperoxide is catalysed very effectively by a titanium complex, produced in situ from a titanium alkoxide and a chiral binaphthol, with enantioselectivities up to 96%342. The Sharpless oxidation of aryl cinnamyl selenides 217 gave a chiral 1-phenyl-2-propen-l-ol (218) via an asymmetric [2,3] sigmatropic shift (Scheme 4)343. For other titanium-catalysed epoxidations, see Section V.D.l on vanadium catalysis. [Pg.1181]

K. B. Sharpless, T. C. Flood, Oxotransition metal oxidants as mimics for the action of mixed-function oxygenases. "NIH shift" with chromyl reagents, /. Am. Chem. Soc. 93 (1971) 2316. [Pg.93]

In the decade of the 1990s, a significant shift occurred in the way in which new pharmaceuticals were synthesized. Before this time, most of the available methods for the preparation of chiral molecules in enantiomerically pure form were impractical on an industrial scale. Thus, t) pi-cally, racemic mixtures were generated, although in many cases only one of the enantiomers in such mixtures possessed the desired activity. However, fundamental conceptual advances in catalysis changed this situation. Some of the most useful examples are a series of highly enantioselec-tive oxidation reactions of double bonds developed by K. B. Sharpless (see Real Life 5-4). [Pg.512]


See other pages where Sharpless oxidation 1.3 -shift is mentioned: [Pg.261]    [Pg.175]   
See also in sourсe #XX -- [ Pg.605 , Pg.609 , Pg.617 ]




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